Schweinsteiger will complete the formalities of his £15m transfer over the next 24 hours after ending his 17-year association with the German club, where he emerged through the youth ranks.

The Germany international, 30, wrote a goodbye letter to Bayern fans on social media in which he attempted to explain his decision to move to the Premier League.

"I hope you understand my decision," Schweinsteiger said. "No one can take away the incredible journey we had together.

"After 17 incredible years at Bayern, 15 national titles, winning the historic treble and uncountable other highlights I was fortunate enough to experience, I have decided to take a new career step."

The prospect of reuniting with Louis van Gaal, who managed Schweinsteiger in Munich between 2009 and 2011, appears to have been crucial in convincing him to make the move.

United have also recruited Torino defender Matteo Darmian and are still interested in Southampton's Morgan Schneiderlin. However, the Old Trafford club face a struggle to retain goalkeeper David de Gea.

Real Madrid's decision to allow Iker Casillas to move to Porto is sure to lead to intensified efforts to recruit the United goalkeeper.